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US3297945A - Detector roll and roll assembly for contacting sized web material for preventing the accumulation of size thereon - Google Patents

Detector roll and roll assembly for contacting sized web material for preventing the accumulation of size thereon Download PDF

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Publication number
US3297945A
US3297945A US296809A US29680963A US3297945A US 3297945 A US3297945 A US 3297945A US 296809 A US296809 A US 296809A US 29680963 A US29680963 A US 29680963A US 3297945 A US3297945 A US 3297945A
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Prior art keywords
roll
web
rolls
contacting
detector
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US296809A
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Jr Charles F Strandberg
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STRANDBERG ENG LAB Inc
STRANDBERG ENGINEERING LABORATORIES Inc
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STRANDBERG ENG LAB Inc
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    • GPHYSICS
    • G01MEASURING; TESTING
    • G01NINVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N27/00Investigating or analysing materials by the use of electric, electrochemical, or magnetic means
    • G01N27/02Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating impedance
    • G01N27/04Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating impedance by investigating resistance
    • G01N27/048Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating impedance by investigating resistance for determining moisture content of the material

Definitions

  • the detector roll of the invention may be used in many different environments where a mechanical and electrical contact with a moving web is desired, the invention is particularly suitable for use in the Apparatus for Measuring and Controlling the Amount of Size and Finish Applied to Textile Yarns and Fabrics, disclosed in my. co-pending Patent application Serial No. 211,508 filed July 23, 1962 now Patent No. 3,207,125.
  • the apparatus disclosed in that application utilizes ordinary metal detector rolls for establishing electrical contact with the web, so that moisture content of the web may be measured and controlled by the apparatus. While such metal detector rolls function quite satisfactorily with most fabrics treated with finishes, they present some problems when applied to fabrics and warps treated with starch size compounds. The wet starch tends to adhere to the metal rolls, particularly along the side edges of the web where the starch congeals faster than in the mid-portion of the Web due to greater heat loss to the surrounding atmosphere.
  • the principal object of the present invention is to eliminate this difiiculty which arises from adhesion of starched fabrics to the rolls.
  • This object is attained by the provision of a detector roll which has a metallic intermediate portion for electrically contacting the midportion of the web, but diametrically reduced end portions equipped with sleeves of plastic material such as Teflon, to which the side edge portions of the starched web do not adhere.
  • the invention provides means for rotating the detector roll in a direction opposite to the direction of travel of the web, whereby to prevent adhesion of the web to the mid-portion of the roll which has an exposed metal surface, and render the metal surface self-cleaning.
  • Another object of the invention is to provide a detector roll assembly consisting of two spaced parallel rolls, adapted to contact the moving web in two planes, spaced longitudinally of the direction of travel of the web.
  • Another object of the invention is to provide a novel brush arrangement for electrically contacting the rolls themselves.
  • FIGURE 1 is a top plan view of a detector roll assembly in accordance with the invention, the web being shown by dotted lines;
  • FIGURE 2 is a side elevational view thereof
  • FIGURE 3 is a cross-sectional view, taken substantially in the plane of the line 3-3 in FIGURE 1;
  • FIGURE 4 is a fragmentary, enlarged sectional detail showing the end portion of one of the rolls with its associated suppport and bearing means and brush means,
  • the detector roll assembly in accordance with the invention is designated generally by the reference numeral 10 and includes a pair of spaced parallel rolls 11 which are adapted to mechanically and electrically engage a moving web 12 in planes spaced longitudinally of the path of movement of the web, as will be readily apparent from FIGURE 3 wherein the web is shown as travelling over the two rolls 11 in the direction of the arrows 13.
  • the two rolls 11 are identical in construction, so that a description of one will suflice for both.
  • Each roll 11 is for-med from electrically conductive material (metal) and includes an intermediate portion 11 and a pair of end portions 11" which are smaller in diameter than the intermediate portion.
  • a pair of tubular sleeeves 14 of suitable material, preferably Teflon, are mounted on the respective end portions 11 of the roll, the outer surfaces of these sleeves being flush with the intermediate portion 11 so that the roll as a whole has a smooth surface.
  • the two rolls 11 are rotatably supported by a pair of upstanding supports or blocks 15, 16 at the ends of an elongated base 17.
  • the blocks 15, 16 are formed from suitable insulating material and are formed with transverse openings 18 to freely receive journals 19 which are formed integrally with the rolls 11 at the ends of the latter.
  • the journals themselves are rotatably mounted by anti-friction bearings 20 held in bearing blocks 21 secured to the inner surfaces of the supports 15, 16 which face the ends of the rolls 11, as will be clearly apparent from FIGURE 4.
  • the support 15 is also provided with a pair of vertical bores 22 which slidably receive brushes 23 and springs 24 which urge the brushes in contact with the adjacent journals 19 of the respective rolls 11, it being noted that the bores 22 at their lower end communicate with the openings 18 to make contact of the brushes with the journal possible.
  • the brushes 23 are connected by flexible conductors 25 to metallic terminals 26 which are secured to the upper edge of the support 15 and serve to retain the springs 24 and the brushes 23 in the bores 22.
  • the terminals 26 serve for connection of suitable current conductors (not shown) to terminal screws 27 with which the terminals 26 are equipped. It will be apparent that the two brushes establish electrical connection to the two rolls 11 separately of each other, as facilitated by the insulating properties of the support 15. Moreover, this electrical connection is taken to or from the web 12 in two longitudinally spaced planes by the intermediate portions 11' of the two rolls 11, which portions have an exposed metal surface in contact with the web, as already explained.
  • means are provided for preventing the midportions of the starched web from adhering to the intermediate-portions 11' of the rolls, such means involving a motor drive for rotating the rolls in a direction which is relatively opposite to the direction of travel of the web, that is, in the direction shown by the arrows 28 in FIG- URE 3, as distinguished from the direction of travel of the web indicated at 13.
  • the motor drive for the rolls comprises a suitable motor 29 which is mounted on an angle bracket 30 attached to the outer surface of the support 15, the armature of the motor carrying a pulley 31 which is connected by an endless belt 32 to pulleys 33 afiixed to the roll journals 19 which pass through the block 15.
  • the belt 32 passes through a suitable slot or opening 34 formed in the bracket 30, and it will be apparent that when the motor 29 is in operation, rotation of the rolls 11 in the opposite direction relative to the direction of travel of the web will effectively prevent the starched web from adhering to the roll portions 11'. In addition, a selfcleaning action of the rolls will result.
  • the rolls are rotated so that their surface speed is approximately one-quarter the speed of the travelling web 12, but in the opposite direction as already noted.
  • a roll for mechanically and electrically contacting a moving coating web said roll being formed from electrically conductive material and having an intermediate portion and a pair of end portions of a smaller diameter than the intermediate portion, a pair of sleeves of plastic material which is more resistant to the adherence of the coating on said web than is the material of said roll provided on the respective end portions and having their outer surfaces fiush with said intermediate portion, means at the ends of said roll journalling the same for rotation, and electrical contact means contacting said roll.
  • said means journalling said roll for rotation comprise -a pair of supports, a pair of journals provided at the ends of the roll, and bearing means carried by said supports and having said journals rotatable therein, said electrical contact means being carried by one of said supports and engaging the associated one of said journals.
  • said electrical contact means including a spring-pressed brush movably mounted in said one of said supports and engaging the associated one of said journals.
  • a roll assembly for mechanically and electrically contacting a moving coated web in planes spaced longitudinally along the path of movement of the web, said roll assembly comprising a pair of spaced parallel rolls, each of said rolls being formed from electrically conductive material and having an intermediate portion and a pair of end portions of a smaller diameter than the intermediate portion, pairs of tubular sleeves of plastic material which is more resistant to the adherence of the coating on said web than is the material of said roll provided von said end portions of the respective rolls and having outer surfaces flush with the intermediate portions, integral journals provided at the ends of said rolls, supports of insulating material having said journals rotatable therein, and electrical contact means carried by one of said supports and engaging the associated journals of the respective rolls, each roll separately from the other.
  • said electrical contact means include a pair of spring-pressed brushes movably mounted in and insulated from each other by said one of said supports, said brushes engaging the associated journals of the respective rolls.

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  • Chemical & Material Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Electrochemistry (AREA)
  • Physics & Mathematics (AREA)
  • Health & Medical Sciences (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Analytical Chemistry (AREA)
  • Biochemistry (AREA)
  • General Health & Medical Sciences (AREA)
  • General Physics & Mathematics (AREA)
  • Immunology (AREA)
  • Pathology (AREA)
  • Elimination Of Static Electricity (AREA)

Description

c. F. STRANDBERG, JR DETECTOR ROLL AND ROLL ASSEMBLY FOR CONTACTING 51 3,297,945 ZED WEB Jan. 10, 1967 MATERIAL FOR PREVENTING THE ACCUMULATION OF SIZE THEREON Filed July 22, 1963 INVENTOR:
United States Fat-eat Gfifice 3,297,945 iPatentecl Jan. 10, 1967 DETECTOR RULL AND ROLL ASSEMBLY FOR CONTACTENG SIZED WEB MATERIAL FOR PRE- VENTING T H E ACCUMULATHON F SIZE THEREON Charles F. Strandberg, Jr., Greensboro, N.C., assignor to Strandberg Engineering Laboratories, Inc., Greensboro, N.C., a corporation of North Carolina Filed July 22, 1963, Ser. No. 296,809 7 Claims. (Cl. 32461) This invention relates to new and useful improvements in so-called detector rolls which are used for mechanically and electrically contacting a moving web of material, such as for example textile yarns and fabrics.
Although the detector roll of the invention may be used in many different environments where a mechanical and electrical contact with a moving web is desired, the invention is particularly suitable for use in the Apparatus for Measuring and Controlling the Amount of Size and Finish Applied to Textile Yarns and Fabrics, disclosed in my. co-pending Patent application Serial No. 211,508 filed July 23, 1962 now Patent No. 3,207,125.
The apparatus disclosed in that application utilizes ordinary metal detector rolls for establishing electrical contact with the web, so that moisture content of the web may be measured and controlled by the apparatus. While such metal detector rolls function quite satisfactorily with most fabrics treated with finishes, they present some problems when applied to fabrics and warps treated with starch size compounds. The wet starch tends to adhere to the metal rolls, particularly along the side edges of the web where the starch congeals faster than in the mid-portion of the Web due to greater heat loss to the surrounding atmosphere.
The principal object of the present invention is to eliminate this difiiculty which arises from adhesion of starched fabrics to the rolls. This object is attained by the provision of a detector roll which has a metallic intermediate portion for electrically contacting the midportion of the web, but diametrically reduced end portions equipped with sleeves of plastic material such as Teflon, to which the side edge portions of the starched web do not adhere. Moreover, the invention provides means for rotating the detector roll in a direction opposite to the direction of travel of the web, whereby to prevent adhesion of the web to the mid-portion of the roll which has an exposed metal surface, and render the metal surface self-cleaning.
Another object of the invention is to provide a detector roll assembly consisting of two spaced parallel rolls, adapted to contact the moving web in two planes, spaced longitudinally of the direction of travel of the web.
Another object of the invention is to provide a novel brush arrangement for electrically contacting the rolls themselves.
With the foregoing more important objects and features in view and such other objects and features as may become apparent as this specification proceeds, the invention will be understood from the following description taken with the accompanying drawings, wherein like characters of reference are used to designate like parts, and wherein:
FIGURE 1 is a top plan view of a detector roll assembly in accordance with the invention, the web being shown by dotted lines;
FIGURE 2 is a side elevational view thereof;
FIGURE 3 is a cross-sectional view, taken substantially in the plane of the line 3-3 in FIGURE 1; and
FIGURE 4 is a fragmentary, enlarged sectional detail showing the end portion of one of the rolls with its associated suppport and bearing means and brush means,
the motor and drive connection to the roll being omitted for sake of clarity.
Referring now to the accompanying drawings in detail, the detector roll assembly in accordance with the invention is designated generally by the reference numeral 10 and includes a pair of spaced parallel rolls 11 which are adapted to mechanically and electrically engage a moving web 12 in planes spaced longitudinally of the path of movement of the web, as will be readily apparent from FIGURE 3 wherein the web is shown as travelling over the two rolls 11 in the direction of the arrows 13.
The two rolls 11 are identical in construction, so that a description of one will suflice for both. Each roll 11 is for-med from electrically conductive material (metal) and includes an intermediate portion 11 and a pair of end portions 11" which are smaller in diameter than the intermediate portion. A pair of tubular sleeeves 14 of suitable material, preferably Teflon, are mounted on the respective end portions 11 of the roll, the outer surfaces of these sleeves being flush with the intermediate portion 11 so that the roll as a whole has a smooth surface.
The two rolls 11 are rotatably supported by a pair of upstanding supports or blocks 15, 16 at the ends of an elongated base 17. The blocks 15, 16 are formed from suitable insulating material and are formed with transverse openings 18 to freely receive journals 19 which are formed integrally with the rolls 11 at the ends of the latter. The journals themselves are rotatably mounted by anti-friction bearings 20 held in bearing blocks 21 secured to the inner surfaces of the supports 15, 16 which face the ends of the rolls 11, as will be clearly apparent from FIGURE 4.
The support 15 is also provided with a pair of vertical bores 22 which slidably receive brushes 23 and springs 24 which urge the brushes in contact with the adjacent journals 19 of the respective rolls 11, it being noted that the bores 22 at their lower end communicate with the openings 18 to make contact of the brushes with the journal possible. The brushes 23 are connected by flexible conductors 25 to metallic terminals 26 which are secured to the upper edge of the support 15 and serve to retain the springs 24 and the brushes 23 in the bores 22. In addition, the terminals 26 serve for connection of suitable current conductors (not shown) to terminal screws 27 with which the terminals 26 are equipped. It will be apparent that the two brushes establish electrical connection to the two rolls 11 separately of each other, as facilitated by the insulating properties of the support 15. Moreover, this electrical connection is taken to or from the web 12 in two longitudinally spaced planes by the intermediate portions 11' of the two rolls 11, which portions have an exposed metal surface in contact with the web, as already explained.
When the apparatus is used in connection with a wet, starched web, the side edge portions of the web will pass over the Teflon sleeves 14 of the rolls 11 as indicated in FIGURE 1 and will not adhere thereto as they would to a metal roll. Of course, the mid-portion of the web will still be in contact with the metallic intermediate portion 11' of the rolls, such contact being necessary for the detection, measuring and control purposes of the apparatus. However, means are provided for preventing the midportions of the starched web from adhering to the intermediate-portions 11' of the rolls, such means involving a motor drive for rotating the rolls in a direction which is relatively opposite to the direction of travel of the web, that is, in the direction shown by the arrows 28 in FIG- URE 3, as distinguished from the direction of travel of the web indicated at 13.
The motor drive for the rolls comprises a suitable motor 29 which is mounted on an angle bracket 30 attached to the outer surface of the support 15, the armature of the motor carrying a pulley 31 which is connected by an endless belt 32 to pulleys 33 afiixed to the roll journals 19 which pass through the block 15. The belt 32 passes through a suitable slot or opening 34 formed in the bracket 30, and it will be apparent that when the motor 29 is in operation, rotation of the rolls 11 in the opposite direction relative to the direction of travel of the web will effectively prevent the starched web from adhering to the roll portions 11'. In addition, a selfcleaning action of the rolls will result. The rolls are rotated so that their surface speed is approximately one-quarter the speed of the travelling web 12, but in the opposite direction as already noted.
While in the foregoing there has been described and shown the preferred embodiment of the invention, various modifications may become apparent to those skilled in the art to which the invention relates. Accordingly, it is not desired to limit the invention to this disclosure and various modifications and equivalents may be resorted to, falling within the spirit and scope of the invention as claimed.
What is claimed as new is:
1. A roll for mechanically and electrically contacting a moving coating web, said roll being formed from electrically conductive material and having an intermediate portion and a pair of end portions of a smaller diameter than the intermediate portion, a pair of sleeves of plastic material which is more resistant to the adherence of the coating on said web than is the material of said roll provided on the respective end portions and having their outer surfaces fiush with said intermediate portion, means at the ends of said roll journalling the same for rotation, and electrical contact means contacting said roll.
2. The structure as defined in claim 1 wherein said means journalling said roll for rotation comprise -a pair of supports, a pair of journals provided at the ends of the roll, and bearing means carried by said supports and having said journals rotatable therein, said electrical contact means being carried by one of said supports and engaging the associated one of said journals.
3. The structure as defined in claim 2 wherein said electrical contact means including a spring-pressed brush movably mounted in said one of said supports and engaging the associated one of said journals.
4. The structure as defined in claim 1 together with means for rotating said roll in a direction opposite to the direction of movement of a Web in contact with the roll.
5. A roll assembly for mechanically and electrically contacting a moving coated web in planes spaced longitudinally along the path of movement of the web, said roll assembly comprising a pair of spaced parallel rolls, each of said rolls being formed from electrically conductive material and having an intermediate portion and a pair of end portions of a smaller diameter than the intermediate portion, pairs of tubular sleeves of plastic material which is more resistant to the adherence of the coating on said web than is the material of said roll provided von said end portions of the respective rolls and having outer surfaces flush with the intermediate portions, integral journals provided at the ends of said rolls, supports of insulating material having said journals rotatable therein, and electrical contact means carried by one of said supports and engaging the associated journals of the respective rolls, each roll separately from the other.
6. The structure as defined in claim 5 wherein said electrical contact means include a pair of spring-pressed brushes movably mounted in and insulated from each other by said one of said supports, said brushes engaging the associated journals of the respective rolls.
7. The structure as defined in claim 5 together with means for rotating said rolls in a direction opposite to the direction of movement of a web in contact with the rolls.
References Cited by the Examiner UNITED STATES PATENTS 1,212,014 1/1917 Butts 324-- 2,735,065 2/1956 Mueller 324-62 3,186,838 6/1965 Graft et a1 15l.5
WALTER L. CARLSON, Primary Examiner.
W. H. BUCKLER, E. E. KUBASIEWICZ,
Assistant Examiners.

Claims (1)

1. A ROLL FOR MECHANICALLY AND ELECTRICALLY CONTACTING A MOVING COATING WEB, SAID ROLL BEING FORMED FROM ELECTRICALLY CONDUCTIVE MATERIAL AND HAVING AN INTERMEDIATE PORTION AND A PAIR OF END PORTIONS OF A SMALLER DIAMETER THAN THE INTERMEDIATE PORTION, A PAIR OF SLEEVES OF PLASTIC MATERIAL WHICH IS MORE RESISTANT TO THE ADHERENCE OF THE COATING ON SAID WEB THAN IS THE MATERIAL OF SAID ROLL PROVIDED ON THE RESPECTIVE END PORTIONS AND HAVING THEIR OUTER SURFACES FLUSH WITH SAID INTERMEDIATE PORTION, MEANS AT THE ENDS OF SAID ROLL JOURNALLING THE SAME FOR ROTATION, AND ELECTRICAL CONTACT MEANS CONTACTING SAID ROLL.
US296809A 1963-07-22 1963-07-22 Detector roll and roll assembly for contacting sized web material for preventing the accumulation of size thereon Expired - Lifetime US3297945A (en)

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Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3465243A (en) * 1966-12-22 1969-09-02 Kingsbury Technology Inc Measurement of capacitivity of materials utilizing a shield
US4717870A (en) * 1982-03-26 1988-01-05 Burlington Industries, Inc. Slasher moisture monitoring system

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1212014A (en) * 1915-09-11 1917-01-09 Edward P Butts Process and apparatus for drying.
US2735065A (en) * 1956-02-14 mueller
US3186838A (en) * 1960-12-27 1965-06-01 Xerox Corp Xerographic plate cleaning method utilizing the relative movement of a cleaning web

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2735065A (en) * 1956-02-14 mueller
US1212014A (en) * 1915-09-11 1917-01-09 Edward P Butts Process and apparatus for drying.
US3186838A (en) * 1960-12-27 1965-06-01 Xerox Corp Xerographic plate cleaning method utilizing the relative movement of a cleaning web

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3465243A (en) * 1966-12-22 1969-09-02 Kingsbury Technology Inc Measurement of capacitivity of materials utilizing a shield
US4717870A (en) * 1982-03-26 1988-01-05 Burlington Industries, Inc. Slasher moisture monitoring system

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